Adds a flag to support "Virtual Time" to the blink scheduler

components/scheduler/test/lazy_scheduler_message_loop_delegate_for_tests.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/scheduler/test/lazy_scheduler_message_loop_delegate_for_tests.h"
 
+#include "base/time/default_tick_clock.h"
+
 namespace scheduler {
 
 // static
 scoped_refptr<LazySchedulerMessageLoopDelegateForTests>
 LazySchedulerMessageLoopDelegateForTests::Create() {
   return make_scoped_refptr(new LazySchedulerMessageLoopDelegateForTests());
 }
 
 LazySchedulerMessageLoopDelegateForTests::
     LazySchedulerMessageLoopDelegateForTests()
     : message_loop_(base::MessageLoop::current()),
-      thread_id_(base::PlatformThread::CurrentId()) {
+      thread_id_(base::PlatformThread::CurrentId()),
+      time_source_(make_scoped_ptr(new base::DefaultTickClock())) {
   if (message_loop_)
     original_task_runner_ = message_loop_->task_runner();
 }
 
 LazySchedulerMessageLoopDelegateForTests::
     ~LazySchedulerMessageLoopDelegateForTests() {
   RestoreDefaultTaskRunner();
 }
 
 base::MessageLoop* LazySchedulerMessageLoopDelegateForTests::EnsureMessageLoop()
@@ skipping 46 matching lines @@
 
 bool LazySchedulerMessageLoopDelegateForTests::RunsTasksOnCurrentThread()
     const {
   return thread_id_ == base::PlatformThread::CurrentId();
 }
 
 bool LazySchedulerMessageLoopDelegateForTests::IsNested() const {
   return EnsureMessageLoop()->IsNested();
 }
 
+base::TimeTicks LazySchedulerMessageLoopDelegateForTests::NowTicks() {
+  return time_source_->NowTicks();
+}
+
+void LazySchedulerMessageLoopDelegateForTests::OnNoMoreImmediateWork() {}
+
 }  // namespace scheduler